By Michael Balogh (CATAC Chair)
(Cassiopeia – Winter/hivers 2017)
The TMT Science Forum was held in Mysore, India on November 7-10. This is the first time one of these meetings took place in India, and it again proved a very effective venue for helping the partner communities become engaged with the project. The focus this year was on TMT instrumentation beyond first light. As announced in the last issue of e-Cass, TMT has issued a call for White Papers due March 21, 2018. These will be reviewed by the SAC, who will make recommendations for the next instrument(s) after first light. The Science Forum provided an opportunity to kick off some of the discussion. Talks are available here. There were also supporting workshops, held on November 6, for discussing three capabilities: a Planetary Science Imager, high resolution spectroscopy, and the first-light instrument WFOS.
At the last SAC meeting, some important updates were provided on both first light instruments for TMT: the infrared imaging spectrograph (IRIS) and the wide-field optical spectrograph (WFOS). In both cases there are decisions being made now, described below, that should be important to the Canadian community. CATAC is therefore following these developments closely.
IRIS successfully completed the second part of its Preliminary Design Review in September; reviews were very positive. The review focused on IRIS observing modes, its interaction with the AO system (NFIRAOS) and the data reduction system. As a result of the review, the IRIS science team is now discussing details of how observations will be taken, and how data will be reduced. NIRIS coupled with NFIRAOS is a very powerful, but complex, instrument that we expect to be of great interest to the Canadian community. If you are interested in knowing more, or would like to get involved, you are strongly encouraged to get in touch with one of the Canadian science team members: Tim Davidge, Pat Coté, or Christian Marois.
WFOS remains a very exciting and challenging instrument. Having earlier abandoned the original concept (MOBIE), the project is now currently considering two very different designs. One would use image slicers, robotically mounted onto masks, to enable multiobject spectroscopy up to high resolution (R~10,000) with narrow slits. The other is a fibre-based design that would allow patrol of the full field, but also bundling to make integral field units. Both designs have advantages and limitations. CATAC will be meeting with the PI of WFOS, Kevin Bundy, on Dec 19 to learn more about the risks and advantages offered by each approach, and the science input driving the specifications. We anticipate that early in 2018 we will be engaging you, the community, to ensure our Science team and SAC members are best able to represent Canadian interests at the time of this important decision.
In addition to these exciting developments, TMT has recently contracted a design study for a secondary adaptive mirror. Studies are underway to predict the improvement in performance as a function of wavelength, natural seeing and field of view. New simulation results will be presented at the next SAC meeting, in Feb 2018. Though this is unlikely to be a first light capability, it could be a priority for an upgrade not long after commissioning.
The political and legal situation in Hawai’i remains generally positive. Legal challenges remain. These are out of our hands and are being dealt with in the courts. The critical issue now is the time it takes to resolve these cases, but the Project remains optimistic that a site decision will be made in April 2018.
To help inform the community on the funding situation facing TMT, on Sept 26 CATAC hosted a public Webex with Ed Stone (Executive Director) and Gary Sanders (Project Manager). Over thirty CASCA members attended. We were presented with a frank and open description of the TMT budget and construction plans. One important takeaway from that meeting was how much impressive work is currently being done, by all partners, despite the delays. About 70% of the items are under contract right now, and roughly 10% of the project is complete. We also got a detailed description of how the project is costed, and how those costs are being revised. There is of course a significant funding gap, that is understood, and the plan submitted to the NSF included a set of options for staging the project. Further discussions with NSF, however, await a site decision.